protodef/example.js

A simple yet powerful way to define binary protocols

const ProtoDef = require("protodef").ProtoDef;
const Serializer = require("protodef").Serializer;
const Parser = require("protodef").Parser;

// the protocol can be in a separate json file
const example_protocol={
  "container": "native",
  "varint": "native",
  "byte": "native",
  "bool": "native",
  "switch": "native",
  "entity_look": [
    "container",
    [
      {
        "name": "entityId",
        "type": "varint"
      },
      {
        "name": "yaw",
        "type": "i8"
      },
      {
        "name": "pitch",
        "type": "i8"
      },
      {
        "name": "onGround",
        "type": "bool"
      }
    ]
  ],
  "packet": [
    "container",
    [
      {
        "name": "name",
        "type": [
          "mapper",
          {
            "type": "varint",
            "mappings": {
              "22": "entity_look"
            }
          }
        ]
      },
      {
        "name": "params",
        "type": [
          "switch",
          {
            "compareTo": "name",
            "fields": {
              "entity_look": "entity_look"
            }
          }
        ]
      }
    ]
  ]
};

const proto = new ProtoDef();
proto.addTypes(example_protocol);
const parser = new Parser(proto, "packet");
const serializer = new Serializer(proto, "packet");

serializer.write({
  name: "entity_look",
  params: {
    "entityId": 1,
    "yaw": 1,
    "pitch": 1,
    "onGround": true
  }
});
serializer.pipe(parser);

parser.on('data', function (chunk) {
  console.log(JSON.stringify(chunk, null, 2));
});